1. Field of the Invention
This invention relates to power transmission belts and, more particularly, to a power transmission belt in which short fibers are embedded.
2. Background Art
V-ribbed power transmission belts have a wide range of uses. They are commonly used in the automotive industry, on agricultural equipment, home appliances, etc.
V-ribbed belts are normally wound around pulleys with grooves that are complementary to the V-shaped ribs on the belt. Power transmission is effected by making use of frictional forces generated between the surfaces on the ribs of the belt and confronting pulley surfaces. It is known to embed short fibers in the ribbed portions of V-ribbed belts to improve resistance to pressure applied laterally to the ribs in use and to reinforce the ribs. Typically, the fibers are directed in a lateral direction, i.e. perpendicular to the length of the belt.
In some systems, the inside surface of the V-ribbed belt is used to drive/be driven by a flat pulley. The inside belt surface, with the laterally extending fibers, is compressed by the cooperating pulley surface.
Because the fibers extend in a lateral direction, they dislodge readily from the inside belt surface during manufacture. Grinding of the inside surface of the belt tends to draw off any exposed fibers so that no significant amount of the laterally extending fibers remains exposed on the inside surface of the completed belt. As a result, a cooperating flat pulley will engage principally the rubber within which the fibers are embedded so that the frictional forces between the belt and pulley are significantly larger than they would be if the fiber was exposed. As a result, significant "creak noise"/"stick slip noise" is generated as slippage occurs between the belt and pulley.